HONG KONG (NYTIMES) - Seething with anger, the black-clad students hurled petrol bombs, threw bricks and even aimed flaming arrows at riot police, who answered with tear-gas volleys and rubber bullets that hurtled into Hong Kong's university grounds for the first time.
And with those battles on Monday and Tuesday (Nov 11 and 12) at the territory's largest universities, another unspoken rule in the anti-government protests that have been convulsing Hong Kong for six months was shattered: the sanctity of educational campuses.
The clashes turned what had been the refuge for the students at the core of the movement into scenes that evoked mediaeval citadels under siege.
They opened a new chapter that threatens to further disrupt the Asian financial capital, which has struggled for normalcy despite the increasingly violent protests against the Chinese communist authorities in Beijing who have the last word over Hong Kong's future.
Hong Kong has fallen into recession as tourists fled and its busy shopping areas became backdrops for street battles between demonstrators and police officers. The world is asking hard questions about what could befall Hong Kong as Beijing further tightens control over a city that is supposed to operate under its own laws.
The most dramatic student-versus-police clash unfolded late on Tuesday night at a barricaded bridge leading to the campus of the Chinese University of Hong Kong. For hours, police officers fired hundreds of rounds of tear gas and rubber bullets and students hurled Molotov cocktails and bricks, and practised firing bows with flaming arrows. More than 100 injured students were taken to a makeshift first-aid clinic in a gym.
By targeting campuses, police breached the last refuge of the protesters, a move that invokes the pivotal and fraught role of student activism in the global history of democracy movements.
"One thing that people have realised is that the protests, the movement, the conflict, is unavoidable," Gabriel Fung, a 19-year-old second-year student at the University of Hong Kong, said.
"It's going to reach you wherever you are at some point."
It is at these universities where young leaders and other students have been organising revolts against the Chinese Communist Party and spreading the pro-democracy ideas that undergird the protests. And here, too, that the students discuss the wealth inequality and cultural homogenisation that have led to visions of a bleak future among many of their generation.
In Hong Kong, university administrators and professors now find themselves in a difficult position, trying to preach tolerance and walk a tightrope of furious demands from students, police and government officials. Two schools ended their semesters weeks early on Wednesday.
"Not a single place in Hong Kong is exempt from the rule of law, and that includes universities," Mr John Lee, the secretary for security, said on Wednesday at a news conference.
"Universities are not supposed to be the breeding ground of violence."
The showdown has been brewing for years, going back to the pro-democracy Umbrella Movement of 2014. And the roots of the protests in many ways harken back to social movements elsewhere.
On mainland China, students have led campaigns calling for sweeping political change, notably in 1919 and 1989. In the United States in the late 1960s and early 1970s, violence broke out on campuses during anti-Vietnam War protests, most horrifically at Kent State University in 1970, when Ohio National Guard troops opened fire on students, killing four and injuring nine.
Student activists in Hong Kong have lived by an exhausting weekly rhythm since the movement began in early June: protest on weekends, show up Mondays for class, study for exams and apply for internships or jobs in between it all. Many argue with parents who disagree with their politics or tactics. Hundreds have been arrested in recent months and quickly released by police, as required by law.
It was the death of a university student this month that set off the current round of protests and violence. Chow Tsz Lok, a student at the Hong Kong University of Science and Technology, suffered a fatal injury after falling from a parking garage near a site of police action Nov 4. Thousands attended candlelit memorial rallies last weekend, and his photograph is on posters and makeshift shrines all over campuses because he is now a martyr for other students.
Roiled by the latest unrest, universities cancelled classes from Monday to Friday. That meant protesters have been able to hit the streets at dawn on weekdays after sleeping a few hours. On campus, activists sprayed fresh graffiti, including phrases cursing administrators.
The fraught situation led police officers on Wednesday to organise an evacuation of dozens of mainland Chinese students across the border to Shenzhen, where hotels offered them free rooms.
One graduate student at Hong Kong University said he and others from the mainland still felt safer on campuses than on the streets. He said many students do not openly express pro-Beijing opinions and sometimes avoid speaking loudly in Mandarin, the dominant language back home. He spoke on the condition of anonymity because of the tensions. Some university departments have delayed recruitment drives of mainland and foreign students to come up with new strategies; a drop-off in enrolment by mainland graduate students, who often pay full tuition, would lead to budget problems.
Hong Kong's public universities, which have more than 86,000 undergraduate and nearly 11,000 graduate students, each have distinct characters. That means the students have occupied different roles in the movement, and the protests have played out in different ways on each campus.
The Chinese University of Hong Kong, with 20,000 students, is considered the most radical campus. Most of its students are Cantonese-speaking locals, some of whom live nearby with their parents in dense apartment blocks. And the campus is high in the hills of Sha Tin, isolated from the city centre, which is an hour's ride away by subway.
On Monday, police arrested five students on the campus's edge, administrators said. The next morning, police, still at the border, confronted frontline students, and clashes took place over 20 hours. Professor Rocky S. Tuan, the university president, who has been known for trying to engage with students during the movement, showed up during a lull in the evening to urge the students to be calm.
"You all should know that I really want to help you. I will do everything within my capability," he said. "It is the university's responsibility to maintain peace on campus, not the police."
But as he began walking away, police fired tear gas. Prof Tuan himself was enveloped in the gas. Students set fires to keep the police from advancing, and scores formed human chains to pass along bricks, umbrellas and bottled water to the front lines. Students sitting on one patch of road made petrol bombs as if on an assembly line.
"It was a savage move and a type of police violence when they tried to encroach on the university," said Timothy Chow, 23, an engineering student who graduated in June. "This is why we have to protect our Chinese University of Hong Kong.
"When I saw our compatriots and Chinese University staff being hurt by the police, I felt particularly furious and wanted to come back to defend our university," he added.
At the University of Hong Kong this week, frontline students also set up barricades and, against the advice of professors, threw paving bricks off balconies, even though it is considered the most in line with the establishment of the territory's schools.
Founded in 1911, it is the territory's oldest university. Many of its students are foreigners or Hong Kong residents who attended international schools. English is the main language, and the university aims to open a mainland China campus. Among its alumni are many police commanders and Mrs Carrie Lam, the territory's chief executive who is reviled by protesters.
On Monday, the students were on edge in part because police had taken a student from a dormitory area early that morning.
Liberal law professors Hualing Fu and Johannes Chan urged a group of frontline protesters in masks not to resort to violence and to understand that the struggle for democracy was a lifetime commitment, according to video footage. But one masked woman shouted they had no choice, and asked: "How many people are we going to sacrifice?"
"We are better; we are different," Prof Fu said.
"But we shall not forgive," a young man shouted. "We shall not forget."
On Monday and Tuesday morning, police officers arrived at campus entrances to try to clear the barricades. They fired tear gas but retreated.
Students have called on University of Hong Kong president Xiang Zhang to forcefully condemn police, but he has refrained from doing so, and, unlike Prof Tuan, rarely holds open forums. On occasion, professors have shown up at the front lines to speak to students, as Dr William Hayward, dean of social sciences, did on Tuesday.
"Obviously, as it goes on and as it gets more polarised, this becomes increasingly a challenge," Dr Hayward later said of student engagement. "Some of them do really open up, but at the same time, you know, of course they're trying to figure out - is he on our side or is he trying to silence us?"
As night fell Tuesday, students traded shifts at the barricades, walking past a famous 8m statue of orange corpses, "The Pillar of Shame", that memorialises the 1989 killing of pro-democracy students and workers around Tiananmen Square in Beijing by the Chinese government.